Electronic Control System Signature, ISX and QSX15 Engines – FAULT CODE 398

Actuator Circuit


Overview

CODE REASON EFFECT
Fault Code: 398
PID: S084
SPN: 1245
FMI: 5/5
LAMP: Yellow
SRT: 

Low current or open circuit detected at rear timing actuator circuit.

Engine is run using only the front three cylinders.

Rear Timing Actuator Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The timing actuators are actuated by the electronic control module (ECM) to control fuel metering. Each timing actuator is connected to the ECM by a supply and a return wire. An electrical pulse is sent to the timing actuator from the ECM on the supply wire and returns to the ECM on the return wire. Each solenoid valve is normally closed, and it is only opened by an electrical pulse from the ECM during metering.

Component Location

The rear timing actuator is mounted on the fuel delivery housing. It is the third actuator from the front of the engine.

Shop Talk

The possible failure modes are an open circuit, a short circuit to ground, high actuator resistance, and loss of boost voltage inside of ECM.

Refer to Troubleshooting Fault Code t05-398.

Last Modified:  26-Oct-2010